Watertight portable thermometer



May 4, 1937. E. BARBIER v 2,078,993

WATERTIGHT PORTABLE THERMOMETER Filed June 18, 1936 Patented May 4, 1937 UNITED STATES PATENT OFFICE Application June 18, 1936, Serial No. 85,968 In Luxemburg July 6, 1935 2 Claims.

The present invention relates to watertight thermometers and its object is to devise a watertight portablethermometer which is absolutely reliable, permits of easy reading and is of new, simple, and very appropriate construction.

This thermometer comprises a thin metal cup provided in its center with a. pivot to which is fixed the core of a spiral bi-metallic thermometer, whose needle travels over a dial engraved or printed on the bottom of the cup. The latter is enclosed in a case whose upper edge is bent over so as to press a disc of transparent material against the upper edge of the cup with the interposition of an elastic washer-or a coating of varnish between the forementioned two edges and; the edge of the disc.

The invention provides, by way of simple examples, for various embodiments of the thermometer which are hereafter described and shown in the accompanying drawing, to which reference is made.

In this drawing:-

Fig. 1 is a sectional view of a first embodiment of the object of this invention;

Fig. 2 is a plane view;

Fig. 3 is a sectional view of an alternative.

In a first embodiment, the thermometer (Fig. 1) is made up of a very thin metal cup I, the upper edge of which presents a bent-over fiat portion a intended to serve as a seat for the watertight device adopted.

The bottom of the cup is, preferably, stamped so as to present a boss It in the centre of which is fixed-a pivot 2. This pivot may be fixed with nut 3 or by screwingfriveting or welding.

On this pivot 2 is screwed or friction fitted a core 4 carrying a bi-metallic spiral 5 at the end of which is a needle 6.

At the bottom of the cup is engraved or printed a dial 1 (Fig. 2) over which. the needle 6 moves under the effect of the difierences in temperature which act on the double strip 5.

The cup ,I. is then inserted in the case 8 whichis preferably made of metal and ofsuch diameter that the edge la fits into the case with slight friction. Onthe edge la is placed a washer 9 made of elastic material and on this washer is placed a disc I!) made of transparent material (plastic material, celluloid or other material).

The edge 8a of the case is then bent over in the shape of a rim on disc l0, and the pressure of this rim upon it is suifijciently strong for the elastic washer to be flattened and provides absolute tightness of the cup.

(Cl. Hi -118) It is obvious that the cup I may be lined with a cup ll made of plastic material shown in mixed lines in Figure l or that a simple disc of the same material could line the bottom of the cup between the latter and the bottom of the case when this case has openings.

This is so, for example, when it is desired to give the thermometer some means of hanging up by a strap, a hook or a safety pin. A piece I2 is then cut out of the bottom of the same, and this piece, when bent over makes it possible to fasten apin l3 for example.

The pressure of the rim 89. upon the cup I causes the bottom of the cup to bear down upon the disc of elastic material lining the bottom of the case, and the tightness of the latter is also ensured.

In another embodiment (Fig. 3) the case .8 provides an annular seat 8b on which rests the edge In of the cup I.

The disc l0, made of transparent material, is then placed on the edge In with or without an intermediate washer 9, and the edge 8a is bent over all round so as to press the whole tightly.

In order to ensure better tightness it is possible to use a cellulose varnish or other varnish which should be spread over both faces of the edge of disc I0.

It is obvious that the varnish may be used more extensively for coating all the joints and sticking the assembled parts together.

The fixation of the spiral double strip 5 may be carried out in different ways.

It is likewise possible to conceal the said double strip, and'only allow the needle to appear, by varied means such as rings or designs printed or engraved on the transparent disc at the places where the double strip is to be seen.

It is also possible to mount on core-4 of the hold, in various professions, sports, (swimming, i

skiing, etc.) and for articles for advertising purposes. Produced in small sizes while ensuring a very great accuracy, these thermometers may be placed in a. pocket or hooked on to the garment without causing any inconvenience to those carrying them. 4

What I claim is:

1. In a watertight portable thermometer. a thin metal cup, a pivot fast in the center of this cup, a bi-metal spiral fixed with its central part to the said pivot, a needle formed by the free extremity of said spiral, a dial in said cup to permit of reading the displacements of said needle, a case to receive said cup with said spiral, a disc of transparent material to close the upper part of said case, a fiat border on the upper edge of said cup, a washer of yielding material disposed between said transparent disc and said border, and a border of the case, bent over said transparent disc, to prevent the passage of water between said disc and said cup.

2. In a watertight portable thermometer, a thin metal cup, a pivot fast in the centre of this cup, a bi-metal spiral fixed with its central part to the said pivot, an index on the free extremity of said spiral, a dial in said cup to indicate the displacements of said index, a case to receive said cup, a transparent disc to close the upper-part of said case, a fiat border on the upper edge of said cup,a bent over outer border on said case to maintain the disc applied against the said flat border of the cup, and a tight varnish between said flat border and said disc, to stick said flat border to said disc.

' EMILE BARBIER. 

